“…Thymocytes were obtained by tissue disruption using frosted glass slides, whereas TEC were prepared by enzymatic digestion of whole thymi as described elsewhere (36,37). After enrichment of low-density cells by Percoll gradient for the sorting of TEC, cell subsets were stained with a combination of CD3, CD4, CD8, CD11c, and CD45 (all from PharMingen, San Diego, CA), as well as mAbs 29 (36), G8.8 (38), and CDR1 (39), respectively.…”